Variable-load device



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J. Q MCCUNE VARIABLE LOAD DEVCE Filed Ooi. 14, 1.927

ATTORNEY (f) u1 D:

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equipment ofi' the type known ltlate...

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VAiRlUMBLE-LD EVJECJE.

.application filed Uctober lll, 192'?. Serial No. 226,121.

relates to fluid pressure and more particularly to a brake as the satety 'llhis invention brakes,

car control equipment.77

fin object of my invention is to provide a safety car control equipment with means for varying the braking power according to the load on the car, and to so arrange said means, that the parts of the usual safety car control equipment7 are utilized Without alteration, to control the means tor varying the bralin power. j

Another object oi my invention is to associate a variable load mechanism with the usual safety car control equipment in such a manner that portions oit said equipment Will function to control the variable load mechanism, Without the interventiorL ot any other controlling means.

'Other objects and advantages ot the invention will appear from the following more detailed description.

lin the accompanying drawing, the single ligure illustrates, in diagrammatic form, a liuid pressure brake of the "satety car control type embodying` the invention.

A safety car control equipment oli the usual type is shown in the drawing, comprising in general an emergency valve device 1, a brake valve device EZ, a safety car controller handle device 3, a door engine 4l, a circuit lil) breaker cylinder device 5, a brake cylinder 6, a main reservoir 7, and a sal'iding reservoir 8. According to my invention, there is associated with this safety car control equipment,a variable load brake mechanism 9.

The emergency valve device 1 comprises a casing having' a piston chamber 10 connected to an emergency Vbrake pipe 11 and containing a piston 19.. rllhis device also has a valve chamber 13 containing* a slide valve 141 adapted to be operated by the piston 12. lhe chambers and 13 are connected with the main reservoir 'i' through the pipe and pas- `sages 15. A relay valve piston 1G is associated with the emergency valve device and has the piston chamber 1'?, at one side, connected through a passage and pipe 1.8,ivith the safety car controller handle device 3. The other side olI this relay valve is connected to the circuit breaker cylinder device 5, by a passage and pipe 19.V j

rlthe variable load mechanism 9 may be, in

`ot the supply valve 2a.

many respects, ol the character shown in United @states Letters Patent lilo. 1.505.950, oiI Clyde C. Farmer, dated August Q6, 1,924, and is for the purpose olf automatically regn ulating the brake cylinder pressure in 'either a service or an emergency application of the brakes as the load on the car is increased or decreased. ln the present embodiment oi the invention, this variable load mechanism 9 has been illustrated as comprising a casing With which there is associated a service brake cylinder pressure lin'iiting valve device 20 and an emergency brake Acylinder pressure limiting device 2l.. The valve device 20 comprises a tlc i ble diaphragm 22 adapted to operate a valve 23 Which controls the operation o't a service brake cylinder supply valve 524i normally seating on a seat ring` Q5. 'lhe valve device 21 is similar to the valve device and comprises a flexible diaphragm 26 for operating a valve 27 which controls the operation ol an emergency brake cylinder supply valve 28 normally seating on a seat ring'QE). rlhediapl'iragms 22 and 26, on one side, are subject to the pressures oi adjustable coil springs 30 and 31 respectively, and on the other side, are subject to brake cylinder' pressure as hereinafter more 'fully described, The springs 30 and 31 are autonnitically adjusted in accordance with the Weight ot' the car and the load carried thereby, through the medium of a mechanism substantially the same as that described in the hereinbeitore mentioned patent and i'or this reason a detailed description oi. the mechanism is deemed unnecessary.

llVhen the brake valve 2 is ope fated to etlfect a service application ol the brakes, the main reservoir pipe 15 is connected, through the brake valve, 'With a fistraifrht air pipe 32, which is connected to a passage 33 leading to the outer exposed seated area of the valve 2liand to a chamber 341-, on one side of the valve 24, as Well leading to a chamber 35, on one side oit the diaphragm 22, the valve 23 being interposed in the passage between the chambers Sli and 35. The cham# ber Sill is connected to the emergencyslide valve seat by passages and pipe 36, one oit which passages leads to the inner seated area rlhe slide valve 141: has a cavity 37 which connects the passage 36, of the emergency valve device l, to a passage 38 of the valve device 1, which latter passage-is connected, by a pipe 39, to a passage 40, inthe casing ofthe variable load mechanism, leading to the outer exposed seated area of the supply valve 28 and to a chamber 41 on one side of the diaphragm QG, and also to a chamber 42 on one side ot the valve 28; rlhe chamber 41 is connected to the brake cylinder 6 by a passage and pipe i 43, such passage also leading to the inner seated area et the supply valve 2S.v

Vhen a service application is eilected, fluid underpressure romthe .main reservoir, supplied tothe passage 33, acts upon the exposed outer seated, area ot the valve piston Q4, causing'. it to unseat and permit. the flow of Yliuid to` passage 36, cavity 37 inl the emergency slide valve 1,4, passage 38,' pipe 39,. and pa.-- sagey 4 0. Eli/iid supplied to passage 40 acts upony theA exposed outer.v seated area of the valvepiston 28, causing it to unseat and supplyflluid under pressure to the brake cylinderitlirough passage and pipe 43. Fluid under. pressure supplied` to the brake cylinc er G is alsosnpplied'to the valve piston chamber 34 andto the. ldiaphragm chamber 35 through a, restriction 44 in one of the passages B3, so that, Whenlthe.pressime in the brake cylinder hasbeen'increased to a predetermined degree` corresponding tothe adjustment of` the spring '.in.accordance u ,fith the load on the car, the diaphragm. QZfivill be caused to move distancefsulticient topermit'the valve 23 to close. Any further increase inthe pressure ot fluid inthe passages 33 and chamber 34 nov: acts uponthe spring side ot the valve piston Q4 and causes it to seat on the seat ring 25, thereby cutting .offthe further supply of fluid tothe brake cylinder.

lVlienit is desired to effect anv emergency application the brakes,the brake valve 2 is moved toitsemergenc-y position, which causes vthe emergency pipe 11 and piston chamber, 1Q, of. the emergency valve device 1, to. be vented'to the atmosphere through an exhaust pipe 45, so that, fluid under pressure in the chamber 13 of the emergency valve device Will cause the piston 12 to shift theeinergency slide valve 14 to its emergency position, in which the passage 38 Will be uncovered and 'Huid at` main reservoir pressure inl the piston chamber 13 o1c the emergency valve device 1 nill'tlovv through this .assaffe 38, Jive 39 and-passaee40- and the.

. e. l l i s 7 pressure. of thetiuid thus suppliedto this latter, passage acts upon the exposedouter seated. area ofthe valvepist-onQS, causing 1t tok unseat and supply fluid under main reservoirpressure tothe bralrecylindcrf through passagejandjpipe 43. Fluid atr main reservofirpressure.thus; supplied to the brake cylinder (i, is:v also'. supplied to the valve piston ely jinber'p42 :and to the diaphragm chamber 41 through a vrestriction 46 in one of the passages 4th, sothat Whenthe pressure. in the brake cylinder has been increased to a predetermined degree, corresponding to the adjustment ot the spring 31 in accordance with the load on the car, the diaphragm 2G will be aus-,ed to move a distance suiicicnt to permit the yalve 2T to close. Any further increase in the pressure et lluid in the passage and chamber 42 will act upon thespringr sideot the valve piston 28 and cause it to seat on the seat ring 29, thereby cutting oil the liurther suppliv ot. tluidl to the bralie cylinder` rlie sanding reservoir 8 is connected to the emergency slide valve seat by a pipe and passage 4'?, which when the slide valve 1iis in its normal release position, as shown in the drawing', is connected to the valve chamberpl through a port Ll-S in the slide valve, thus charging the sanding reservoir with fluid at main reservoir. pressure. lVhen the piston 12 and slide valve 14 move in cilenting an emergency application of'. the brakes, a caviry in the slide valve connects the passage 4T to a passage 49 leading to a sand pipe 49, which sand pipe may be provided with the usual sand traps (not shown).A

rThe safety car controller handle device comprises a double seating valve 50, which is movable b v the controller handle of the device to eilect a connection between the ma in reservoir pipe 15 and the pipe 1S, or to vent the pipe 18 to the atmosphere. Should the operator remove his hand trom the controller nandle of this device, the valve 50 will be moved upvardlyv andwill permit the fluid unner pressure in the chamberlion one sigle of the valve piston 1G, ot the en'iergency valve device 1. to exhaust to the atmosphere through passage and pipelS and an atmosf plieric port 51 in the casing et the device 3. Fluid under pressure acting' on the outer seated area ot valve piston 1G. as supplied thereto from the emergency pipe 11 and passage 52 in the emergency alve devi-ne` will non cause the valve piston .i6 to move to its open position, permitting tluid under pressure to Een' from passage 52 and emergen@- pipe 11 tlnfcugh the passage and pipe l!) to the circuit breaker cylinder device causing the piston thereo'in to be operated to openlhe povver circuit in the usual manner. Then this Listen has moved a predetermined distance, apertures 53, in the cylinder et the device, ivill be uncovered and fluid under pressure from the piston chamber 10. ot the emergencyv valvedeviee, will exhaust therethrough to the atmosphere. This results in, the piston 12 and slide valve 14, oi'i the emei-- gency valve device, moving to theireiner genenv positions, after which the operations of" the several parts ot the apparatus are the same as hereinhet'ore described in connection with the et :ecting ofi an emergency application et the brakes.

TNhile one illustrative embodiment. of the inventionhas been described in detail, it is neeaete not my intention to limit its scope to that embodiment or otherwise than by the terms of the appended claims.

Having now described my invention, what l claim as new and desire to secure by liet-ters Patent, is rl. rlhe combination with a safety car control equipment, vof a variable load mechanism associated therewith, andmeans includ ed in said equipment for controlling the flow of iiuid under pressure to said mechanism.

2. rllhe combination with a safety car control equipment, of a variable load mechanism associated therewith, and an emergency valve device included in said equipment for controlling the flow of fluid under pressure to said mechanism.

3. The combination with a safety car control equipment, of a variable load mechanism associated with said equipment and operative by fluid under pressure, when effecting an application of the brake, to vary the braking power in accordance with the load on the car, and valve means forming part ot said equipment adapted to supply fluid under pressure directly to said variable load mechanism in effecting an emergency application o'l the brake.

a.k The combination with a safety car control equipment, of a variable load. mecha` nism associated with said equipment and operative by fluid under pressure, when effectinp an application oit' the brake, to vary the brakingpower in accordance with the load on the car, said mechanism comprising a service limiting portion and an emergency limiting portion, a brake cylinder forming a part of said equipment and connected to said. emergency limiting portion, means included in said equipment for supplying1 fluid under pressure directly to said service limiting portion in effecting a service application of the brake, and valve means forming; part of said equipment adapted to control the flow of fluid under pressure from said service limiting portion to said brake cylinder through said emergency limiting; portion.

5. rllhe combination with a safety car control equipment, of means associated therewith and operative by fluid under pressure when effecting' an emergency application of the brake to vary the braking power in accordance with the load on the car, and an emergency valve device forming part o'l'.' said equipment operative to supply fluid under pressure directly to said means.

d lln a duid pressure brake, the combinaice limiting tion with a variable load mechanism comprisingl a service limiting portion and an emergency limit-ing' portion, of a. brake cylinder connected to said emergency limiting portion, means operative for supplying, fluid under pressure to said service limiting portion, and means for controlling the supply of fluid under pressure from said service limiting portion to said brake cylinder through said emergency limiting; portion.

7. ln a fluid pressure brake, the combination with a. variable load mechanism comprising a. service limiting portion and an emergency limiting portion, of a bralre cylinder connected to said emergency limiting portion, means operative for supplying fluid under pressure to said service limiting portion, and an emergency valve device for controllingn the supply of' fluid under pressure from said servportion to said brake cylinder through said emergency limiting portion when a service application oi the brake is effected and for supplying fluid under pressure to said brake cylinder through said emergency limiting portion only, when an emergency application of the brake is eiiiected.

8. ln al fluid pressure brake, the combination with a. brake cylinder, of' a variable load mechanism comprising,l a service limiting portion adapted to limit the supply of fluid under pressure to said bralre cylinder according,1 to the load on the car, and an emergency limiting portion adapted to limit the supply oi' fluid under pressure to said brake cylinder according to the load on the car, said brake cylinder connected through said emergency limiting,` portion only, and means whereby iluid under pressure is supplied to said brake cylinder through both of said portionswhen a service application of the brake is effected and through said emergency limiting portion only, when an emergency application of the brake is eillected.

9. ln a fluid pressure brake, the combination with a variable load mechanism having a service limiting1 portion and an emergency limitingl portion, of a brake cylinder connected to said emergency limiting` portion and adapted to be supplied with fluid under pressure through both of said limiting portions when a service application of the brake is effected and through the emergency limiting portion only, when an emergency application of the brake is eflected.

lln testimony whereof l my hand.

have hereunto set JSllElPltl C. lllcCllllllE.

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